"I am on a healthy diet."
Translation:Jestem na zdrowej diecie.
Well, literal locations are only one of the usages of Locative. I guess we could figure an interpretation (it is in a way a location? or it is in a way an event?) that could explain it... or we could say that "na" takes either Locative (for location) or Accusative (for movement), and "dieta" undergoes it: we have "jestem na diecie" (I'm on a diet) but "przechodzę na dietę" (Accusative -> I am going on a diet).
This is the first time I'm seeing a Polish word, dieta where the i is not palatalizing a d with dź. Is it because "diet" is a loan word?
I noticed that so far every analogous Russian word that contains дь/ди/де, in Polish contains dź/dzi/dzie.
Incidentally, is there an analogous Polish name for Vadim? Would it be something like "Wadzim"? Or "Wadym" for the Ukrainian version?
I'm not sure if that's exactly what you mean, but there are plenty of words starting with "di" in Polish... I already found diagnoza/диагноз, dialog/диалог or dinozaur/динозавр as PL/RU pairs.
No, I don't believe there is a Polish equivalent, unless someone has Eastern heritage (Wadim Tyszkiewicz - a businessman, but born in Belarus).
That's interesting. The Belarusian name is Вадзім/Vadzim, closer to Polish if anything. Belarusian д palatalized by soft vowels becomes дзь, and palatalized т becomes ць. But Russian is much more spoken in Belarus than Belarusian.
These all seem like loan words diet, diagnose, dialogue, dinosaur, probably Latin roots not Slavonic. Polish is usually dzi/dzie or dy/de, right?